Abstract: Through passively emitting excess heat to the outer space, radiative cooling has been demonstrated as an efficient way for energy saving applications. Instead of well-designed photonic structures, we rediscovered the potential of bulk materials as inrafred emitter for sub-ambient daytime radiative cooling. Two kinds of infrared emitters are proposed in this presentation: one with broadband infrared emission and another with selective infrared emission. The broadband one is composed of bulk polyvinyl fluoride (PVF) layer and Ag coating, and a solar absorptance below 10% and infrared emittance over 90% is achieved. On the other hand, the selective emitter is composed of a 1-mm-thick lithium fluoride crystal coated with Ag backing, and a solar absorptance below 5% and nearly ideal infrared selectivity with high emission exactly within the atmospheric transmission band (i.e., 8–13 μm) could be obtained. Potentially, the proposed selective emitter could reach a very low equilibrium temperature with 57 K below the ambient one. Both theoretical calculations based on energy balance and outdoor tests demonstrated the ability of these two infrared emitters to achieve sub-ambient daytime radiative cooling, which were mainly caused by the intrinsic optical properties of these two bulk materials. More details about the calculation process, experimental setup and cooling performance will be introduced in this presentation. We hope these scalable radiative coolers with low fabrication cost could find broad applications in energy saving areas.